Biomechanical Modeling of Aneurysm Growth and Rupture Using Fluid Structure Interaction

Abstract

We developed a method to analyze aneurysm growth and rupture based on idealized spherical shape from actual patient-specific geometry data. This study was carried out to evaluate whether wall mechanics of soft tissue coupled with blood flow dynamics can be used to provide the insight into the weakening phenomena. In order to simulate the behavior of the system, the fluid structure interaction method (FSI) was utilized using transferred data from the fluid dynamics model to finite element wall mechanics. The FSI transferred these dynamics loads to exert the aneurysms wall whose respective deformations were then determined. The numerical modeling of aneurysms results the blood flow parameter of pressure and velocity inside the aneurysm sac in the form of profile correlations. These parameters generate a possible aneurysm rupture time during the growth as a reasonable quantitative observation. The developed method allows us to identify biomechanical factors that can influence the blood flow property changes and wall stress distributions. As part of the computed maximum wall stress to relate with growth and rupture, normalized velocity and pressure profiles inside the aneurysm sac were correlated. This explains the effect of blood flow to the weakening vessel wall and rupture behaviour due to variable flow conditions. These results assist medical practitioners to the prediction of time and location of ruptured aneurysm.